1. Field of the Invention
The present invention relates in general to solar panels for use in a roof-mounted array and, more particularly, to a solar panel that provides environmental protection to its photovoltaic cells, is easily installed and replaced, and that can serve as a roofing panel eliminating the need for shingles or tar paper.
2. Discussion of the Related Art
It is a known practice to mount solar panel arrays on rooftops where they are most likely to receive a maximum amount of sunlight without interference from trees, buildings or other obstructions. One method for mounting an array of solar panels on a roof is to first assemble the solar panels on a support to form the array, and then to secure the supported array on the existing rooftop. A problem with this mounting method is the difficulty involved with lifting and mounting the array onto the roof without damaging the solar panels. Further, in view of the substantial weight of the assembled array, special equipment is needed to lift the array onto the roof.
Another method for mounting an array of solar panels on a roof is to mount the solar panels individually and directly onto the surface of the roof to form the solar panel array. This method obviates the above described difficulties because it enables the installers to carry the individual solar panels up to the roof and mount them one at a time.
One need that arises in mounting an array of solar panels directly onto a roof is a need for provision of a convenient path for running the electrical conduits which carry the wiring that electrically interconnects the solar panels. U.S. Pat. No. 4,189,881 issued to Hawley, provides a solution to this problem in a batten-seam roofing system constituted by pans which longitudinally extend from the top of the roof to the bottom. The pans are secured to the roof using clips. The clips are placed over the lipped edges of the adjacent pans and screwed into the roof such that the pans are spaced apart. Individual photovoltaic cell modules are mounted on and secured to the long pans. Batten seam caps are placed over the gaps between pans to create channels for the electrical conduits that carry the wiring for the photovoltaic cells.
One possible drawback to such a construction method is the need for additional hardware to secure the photovoltaic cell modules to the pans. Also, mounting the array on the roof involves a two step process of first mounting the pans on the roof and then mounting the photovoltaic cell modules to the pans. Further, because the photovoltaic cell modules must be secured to the pans directly, the likelihood that one of the modules will be damaged is increased.
Another problem with conventional roof-mounted solar panel arrays is their limited ability to endure outside environmental conditions. Roof-mounted solar panels are often damaged by adverse weather conditions, thus increasing the frequency with which they need t be replaced and therefore the cost of maintaining the roof-mounted array.